We propose to recall and study approximately 250 subjects with diabetes both (IDDM and NIDDM) who were identified and characterized in 1990 and found to have normal urinary albumin excretion or microalbuminuria to prospectively test the following: 1) there is a genetic predisposition to the development and progression of diabetic renal disease; 2) certain baseline risk factors (e.g. glycemic control, hypercholesterolemia, smoking, and hypertension) are important in the development and progression of diabetic renal disease; and 3) development and progression of microalbuminuria is associated with other diabetic complications (e.g. retinopathy, neuropathy, and ischemic heart disease).